There are many reasons for promoting aging, but reactive oxygen species (ROS) is considered to be one of the major causes. This ROS is indispensably produced in energy metabolism, immune response, etc., and is generated by inevitable stimulus caused by external harmful environment. ROS is highly reactive to cause DNA degeneration, induction of excessive signal transmission, protein denaturation, etc. in the body, resulting in a series of reactions accumulating adverse health effects.
However, in these harmful conditions, homeostasis have been elaborately maintained by external antioxidants (uric acid, vitamin C, vitamin E, etc.) or endogenous antioxidant enzymes (glutathione peroxidase, superoxide dismutase, catalase, etc.) which present in the body. However, the aging of the antioxidant system due to the endogenous aging and the accumulation of ROS by the continuous and noxious stimuli may break this balance, promoting aging, causing various diseases such as skin diseases, skin cancer, arteriosclerosis, and thrombosis (Laure Rittie et al., Aging Research Reviews, 1, 705-720, 2002; Cutler R G, Annals of the New York Academy of Sciences, 1055, 93-135, 2005).
Accordingly, there is a growing interest in antioxidants that inhibit the formation of reactive oxygen species (ROS) or removing ROS. Antioxidants can be divided into those that are naturally present in the body (endogenous antioxidant) and those that are administered externally (exogenous antioxidant).
Antioxidants that are naturally present in the body include enzymes such as superoxide dismutase (SOD), glutathione, peroxidase, and catalase. Externally administered antioxidants include phytochemicals such as kaempferol, catechin, and genistein; vitamin E, vitamin C, and beta carotene; and minerals such as selenium.
Vitamin C (L-ascorbic acid, ascorbate) is essential for humans and other animals, and is important for collagen synthesis, etc., and is a cofactor for at least eight enzymes. Therefore, vitamin C deficiency causes diseases such as scurvy. In animals, vitamin C is an important factor to prevent wound healing and capillary hemorrhage, and is a critical antioxidant in the body along with vitamin A, vitamin E, and others.
Cells are attacked by free radicals, oxygen free radicals, and etc. caused by ultraviolet A (UVA) and ultraviolet B (UVB) irradiated from, sunlight, pollutants, stress, smoking, drinking, and fatty foods. If the proper protection from these materials is not achieved, the cells will age or die. In the case of skin, the production of materials such as collagen and elastin is reduced or denatured by these materials, causing the skin to lose its elasticity and resulting in wrinkles. In order to prevent this, it is known that it is important to prevent aging of the skin by applying a preparation containing antioxidants such as vitamins A, C, and E to the skin and absorbing it into the skin by preventing oxidation from the harmful environmental factors. However, vitamin C (L-ascorbic acid) is easily oxidized in the air and by sunlight, and thus its antioxidant effect disappears. Therefore, there is a problem in manufacturing various formulations having a long storage period.
Meanwhile, hydrogel refers to a material having a high-water content (90% or more) made of a hydrophilic polymer. There are many kinds of materials such as natural materials (collagen, etc.) and synthesized materials (silicone hydrogels, polyacrylamides, polymacon).
It is highly demanded that the active ingredient is promptly transferred into the skin within a short time of 20 minutes to 30 minutes after the hydrogel is applied to the skin. To do so, the active ingredient in the hydrogel must be promptly and uniformly transferred to the skin.
While the state of the hydrogel is maintained, effective cosmetic ingredients in the gel are limited in sustaining a satisfactory amount and speed to be delivered from the hydrogel to the skin is also very limited. In addition, the water and the active ingredient in the hydrogel are evaporated as time passes so that it is not possible to take its advantages. Therefore, even if the hydrogel has unique adhesiveness and wettability, the limit of the effective ingredient contained in the hydrogel as well as the limit of the delivery speed of the effective cosmetic ingredient to the skin results in restriction of the skin penetration efficiency of the hydrogel mask pack, which is disclosed in Korean Patent No.: 10-1197677.